126821633 has 4 divisors (see below), whose sum is σ = 129214548. Its totient is φ = 124428720.

The previous prime is 126821627. The next prime is 126821647. The reversal of 126821633 is 336128621.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 336128621 = 3343 ⋅100547.

It can be written as a sum of positive squares in 2 ways, for example, as 73136704 + 53684929 = 8552^2 + 7327^2 .

It is a cyclic number.

It is not a de Polignac number, because 126821633 - 2¹⁰ = 126820609 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 126821633.

It is not an unprimeable number, because it can be changed into a prime (126851633) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1196378 + ... + 1196483.

It is an arithmetic number, because the mean of its divisors is an integer number (32303637).

Almost surely, 2^126821633 is an apocalyptic number.

It is an amenable number.

126821633 is a deficient number, since it is larger than the sum of its proper divisors (2392915).

126821633 is an equidigital number, since it uses as much as digits as its factorization.

126821633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2392914.

The product of its digits is 10368, while the sum is 32.

The square root of 126821633 is about 11261.5111330585. The cubic root of 126821633 is about 502.4171400383.

The spelling of 126821633 in words is "one hundred twenty-six million, eight hundred twenty-one thousand, six hundred thirty-three".